Hybrid vehicles that use electric power and fuel to drive their wheels and electric vehicles, such as electric cars, which use only electric power to drive their wheels are known as passenger cars. For example, an in-wheel motor described in Japanese Unexamined Patent Application Publication No. 2005-271909 (Patent Literature 1) is known as an in-wheel motor that is placed in an internal space region of a wheel of an electric vehicle to drive the wheel. In the technique described in Patent Literature 1, a plurality of wires (electrical cables) are inserted and fixed in a wiring box of the in-wheel motor, and these wires are held by a wire clamp. The wire clamp can rotate about a kingpin and thus can restrain stress that is applied to the wires even when the in-wheel motor is displaced with respect to a suspension arm.